Realitybites is right, u shouldn't keep this unattended.

Women have the tendency to be more open about their feelings than guys. U only need to ask and show her that ur sensitive to what she feels.

Women can sometimes be silly creatures.

They tend to tell u she isn't mad but she is SHOWING u that there's something wrong.
Men can sometimes be insensitive. Perhaps because they don't fuss about small things (like women do!

). If u noticed that she is acting "abnormally" then it won't hurt to ask. Believe me, she will likely open up. U have to talk about it to find better solutions to it.

I hope it helps!
God bless!